The Internet is a global system of interconnected computer networks that store a vast array of information. The World Wide Web (WWW) is an information sharing model built on top of the Internet, in which a system of interlinked hypertext documents are accessed using particular protocols (i.e., the Hypertext Transfer Protocol, or HTTP, and its variants).
Because of the enormous volume of information available via the WWW and the Internet, and because the available information is distributed across an enormous number of independently owned and operated networks and servers, locating desired content on the WWW and the Internet presents challenges.
Search engines have been developed to aid users in locating desired content on the Internet. In general, a search engine is a computer program that receives a search query from a user indicative of content desired by the user, and returns information and/or hyperlinks to information that the search engine determines to be relevant to the user's search query.
Search engines typically work by retrieving a large number of web pages and/or other content using a computer program called a webcrawler that browses the World Wide Web in automated fashion (e.g., following every hyperlink that it comes across in each web page that it browses). Retrieved web pages and/or content is analyzed and information about the web pages and/or content is stored in an index. When a user issues a search query to the search engine, the search engine uses the index to identify the web pages and/or content that it determines to best match the user's search query, and returns a list of results with the best-matching web pages and/or content. Frequently, this list is in the form of one or more web pages that include a set of hyperlinks to the web pages and/or content determined to best match the user's query.
There are at least two general types of search engines accessible via the Internet: general-purpose search engines and site-specific search engines. As used herein, the term “general-purpose search engine” is defined to mean a search engine that provides search results that include web pages and/or content (or hyperlinks to web pages and/or content) hosted on at least two different and independent web sites or domains. General purpose search engines attempt to index and provide search results from content distributed across a wide swath of the Internet. Examples of general purpose search engines include Google™, operated by Google, Inc. of Mountain View, Calif.; Yahoo!™, operated by Yahoo!, Inc. of Sunnyvale, Calif.; and Bing™, operated by Microsoft Corp. of Redmond, Wash.
As used herein, the term “site-specific search engine” is defined to mean a search engine that provides search results that include web pages and/or content (or hyperlinks to web pages and/or content) hosted on only one web site or domain. Site-specific search engines are frequently used by operators of web sites to allow users to find specific web pages or content on their web sites. For example, the web site of an online retailer (or “e-tailer”) may include a site-specific search engine that facilitates a user locating web pages for products sold by the retailer.